Thermoelectric apparatus



June 24, 1969 c. J. MOLE THERMOELECTRIC APPARATUS Sheet Original FiledDec. 18, 1964 VII! r NdE M m mm N 5 mm 0w mm m 9 QN 02 0 2 an Cecil J.Mole INVENTOR Sheet 5 H V c m C. J MOLE m m ls Q? v w THERMOELECTR ICAPPARATUS m @K/ g June 24, 1969 Original Filed Dec. 18, 1964 wwwessssSheet FIG. 5.

C. J. MOLE THERMOELECTRIC APPARATUS A A m w e 4 5 3 w a I 0 I I. 2 Q m 2.35: if a 5 0 o m m m. m 4 4 m r 5 /////M f /W w H/ g S 4 I I 5y t F2 ,Ec m m m 2 June 24, 1969 Ongmal Filed Dec.

June 24, 1969 c J MOLE R8. 26,612

THERMOBLECTRIC APPARATUS Original Filed Dec. 18, 1964 Sheet 4 of 4 FIG.6.

Reissued June 24, [969 26,612 THERMOELECTRIC APPARATUS Cecil I. Mole,Murrysville, Pa., assignor to Westinghouse Electric Corporation,Pittsburgh, Pa., a corporation of Pennsylvania Original No. 3,213,630,dated Oct. 26, 1965, Ser. No. 419,405, Dec. 18, 1964. Application forreissue Mar. 15, 1967, Ser. No. 672,941

Int. Cl. F25b 21/02 US. Cl. 62-3 8 Claims Matter enclosed in heavybrackets II] appears in the original patent but forms no part of thisreissue specification; matter printed in italics indicates the additionsmade by reissue.

ABSTRACT OF THE DISCLOSURE A direct transfer apparatus for the efiicientdehumidification of air is provided wherein at least three electricallyconducting heat transfer means are mounted in tandem and having layersof thermoelectric material disposed between and electrically andthermally coupled to adjacent ones of the heat transfer means to providealternate heating and cooling in alternate adjacent heat transfer means.Conduit means form a flow path through the dehumidifier to cause airflow first past the cooled heat transfer means and then past the heatedheat transfer means.

The present invention is directed generally to thermoelectric apparatusand more particularly to the construction of new and efiicieutair-to-air devices for varying the temperature of one of the fluid mediaor for producing through the use of thermoelectric eflects, electricalpower.

In its more specific aspects, this invention is also directed to theconstruction of an improved air-to-air device for dehumidifyingapplication. In addition, this invention is directed to a new andimproved arrangement for mounting the thermoelectric layers of thethermoelectric apparatus to promote the more efficient use thereof whileconcurrently reducing the possibility of electrical arcing therein.

In copending applications Serial No. 320,160, filed October 30, 1963,entitled Thermoelectric Heat Pumping Apparatus, Serial No. 332,010,filed December 20, 1963, and Ser No. 331,997, filed December 20, 1963,both entitled Thermoelectric Apparatus," of which the present inventoris a coinventor, and which have been assigned to the same assignee asthis invention, there have been described thermoelectric arrangements ofthe liquidto-liquid and liquid-to-air types incorporating a novelapproach or principle for obtaining high efliciency at with tiveiy lowcost and for utilizing relatively small amounts of thermoelectricmaterial. The principle of operation of these devices is known as directtransfer" wherein there is provided in the thermoelectric apparatus aheat flow path having no electrical or thermal insulation therein. Withdirect transfer devices, substantially all of the cooling elfects andheating eifects produced at the thermoelectric cold and hot junctionsare transferred directly to the cooled and heated media of thethermoelectric heat exchanger. In the present invention there isprovided a thermoelectric apparatus of the alr-to-air type whichembodies the direct transfer principles to produce an air-toairarrangement having all of the advantages of high efficiency, low costand low material utilizations of direct transfer devices.

Within the contemplation of this invention is also the provision of anair-to-air electrical power producing apparatus utilizing thermoelectriceffects for the direct production of electricity,

Also within the contemplation of this invention is the provision of anair-to-air thermoelectric device of the direct transfer type applied fordehumidification of air Accordingly it is an object of this invention toprovide a new and improved thermoelectric heat exchange device having noelectrical insulation in the heat flow path and being of the air-to-airtype.

Still another object of this invention i to provide a new and improvedthermoelectric generating device of the air-to-air type which promotesthe eflicient generation at electrical power.

A further object of this invention is to provide a thermoelectric devicehaving a new and improved positioning arrangement for the thermoelectricmaterial to minimize the possibility of electrical arcing.

A still further object 05 this invention is to provide a new andimproved air-to-alr thermoelectric exchange dcvice for use as adehumidifier.

Briefly, the present invention accomplishes the abovecited objects byproviding an air-to-air thermoelectric construction or thermopilewherein there is provided a plurality of separated air flow circuitswith at least one of the circuits being coupled in heat exchangerelationship with cooled heat exchange members and the remainingcircuits being coupled in heat exchange relationship with heated heatexchange members. The heat exchange members for all of the circuits forma part of the electrical flow path of the thermoelectric constructionthereby resulting in an arrangement wherein no electrical thermalinsulation is required in the heat flow paths between the thermoelectriclayers and the heated and cooled heat exchangers. In essence, thevarious heat exchangers of the thermoelectric construction actually formthe hot and cold junction members of the thermopile. Insulating meansare positioned in the thermopile to separate electrically adjacent onesof the thermoelectric junctions and thermoelectric layers from oneanother. This arrangement of insulating material results in a currentflow path which extends through each of the thermoelectric layers andjunctions of the thermopile in a generally sinusoidal manner.

In accordance with the invention there is also provided herein anarrangement of the air-tosair thermoelectric device of this inventionfor use in the dehumidification of air so that the separated heated andcooled flow paths through the thermopile are connected in series andresults in the removal of moisture contained in the air flowingtherethrough.

One of the advantages of a direct transfer thermoelectric constructionis the provision of a thermopile wherein relatively thin thermoelectriclayers are positioned be tween closely located yet spaced junctionmembersv The closely spaced junction members promote the possibility ofarcing thcrebetween to bypass the thermoelectric layers. Within thecontemplation of this invention is the provision of a pedestal-typemounting for thermoelectric layers between adjacent junction members toeliminate the possibility of arcing.

Further objects and advantages of this invention and features of noveltywhich characterize the invention will be pointed out in particularity inthe claims annexed to and forming a part of the specification.

For a better understanding of this invention reference may be had to theaccompanying drawings, in which:

FIGURE 1 is a top plan view of an air-to-air thermoelectric heatexchange apparatus embodying the principles of this invention;

FIG. 2 is a sectional view of the thermoelectric heat exchange apparatusof FIG. 1 and taken along the lines lL-ll thereof:

FIG. 3 is another sectional view of the thermoelectric heat exchangeapparatus of FIG. 1 and taken along the lines IIIIII thereof;

FIG. 4 is a schematic view of the electrical flow path through thethermoelectric heat exchange apparatus of FIGS. 1 to 3.

FIG. 5 is a sectional view through a modified form of air-to-airthermoelectric heat exchange apparatus and illustrated in adehumidification application;

FIG. 6 is a side elevational view of a modular air-to-air thermoelectricheat exchange structure and illustrative of another embodiment of thisinvention.

Referring now to the embodiment of this invention i1- lustrated in FIGS.1 through 4, there is shown a thermopile 10 constructed in accordancewith the principles of this invention which includes a plurality ofoutwardly disposed, cooled fin type heat exchangers 12A, 12B and 12Cdisposed on the outer sides of the thermopile -10 and a plurality ofcentrally disposed, heated fin type heat exchangers 14 disposed betweenthe two outer sets of cooled heat exchangers 12. Each of the heatexchangers 12A, 12B and 120 includes a base member 16A, 163 or 16C,respectively, formed from on electrically conducting material and aplurality of laterally extending fins 18 secured to and projectingoutwardly from the bases 16A, 16B and 16C in a spaced, parallel array.Fins 18 are electrically conductive and are contained within a generallyU-shaped housing 20 also formed from electrically conductive material.As will be appreciated from FIGS. 1 through 4, essentially threedifierent types of cooled heat exchangers are utilized with thethermopile -10. One type of heat exchanger 12 is designated by referencecharacter 12A and has a base member 16A sized to have secured theretotwo laterally spaced layers of thermoelectric pellets 21. Each of theheat exchangers 12A is generally rectangular shaped with the fins 18thereof extending laterally from the base in the longitudinal direction.A pair of half-sized heat exchangers 12B are provided in two corners ofthe upper level FIG. 3 of heat exchangers 12. The heat exchangers 12Bconform exactly to the heat exchanger 12A except for their smaller sizeso that heat exchangers 12B receive only one layer of thermoelectricmaterial 21 on the base 16]! thereof. A third type of cooled heatexchanger is formed to bridge adjacent rows of the thermopile l0 and isdesignated generally by the reference character 12C. The heat exchangers12C each have a base 16C on which is mounted a pair of spaced housingmembers 20C which extend laterally therefrom with the fins 18 thereofbeing positioned along the transverse dimension of the bases 16C. FromFIGS. 1 and 4, it will be seen that the upper level of heat exchangers12 comprises four heat exchangers 12A positioned centrally of the upperlevel, two heat exchangers 12B positioned in two corners of the upperlevel and three bridging heat exchangers 12C having bases 16C positionedto bridge adjacent rows of heat exchangers 12. The lower level of cooledheat exchangers l2 merely comprises eight heat exchangers 12A havingbases 16A. As can be seen from FIGS. 1 through 3, all of the cooled heatexchangers 12 forming the upper and lower levels are formed with thefins 18 thereof extending from side to side of the thermopile 10 (i.e.from the righthand side to the left-hand side of FIG. 1). Each of thebases 16A and 16B of heat exchangers 12A and 12C is provided with twolaterally spaced layers 21 of thermoelectric material, such as hismuthtelluride, which are desirably secured to the bases 16A and 16C bysuitable means such as by brazing or soldering. Each of the bases 16B isprovided with only one layer of thermoelectric material 21 similarlysecured thereto. In the illustration of the invention of FIGS. 1, 2 and3, it will be appreciated that each Otf the thermoelectric layers 21 isformed from nine pellets which are individually secured to the adjacentbases so that each set of pellets forms a separate thermoelectric layer.

Each of the layers ot thermoelectric flltlitil'ldl 2| are formed fromeither thermoelectrically positive or thermoelectrically negativematerials with the polarities being selected to form a current flow pathIn thermopile 10 having thermoelectrically positive andthermoelectrically negative material therein in an alternating sequence.Accordingly, as current passes from thermoelectrically positive materialto thermoelectrically negative material, heat is imparted to thestructure or junction member intermediate the positive and negativematerials. Similarly as current passes from thermoelectrically negativeto thermoelectrically positive material, a cooling elfect takes place inthe heat exchange structure between the latter layers of thermoelectricmaterial. As illustrated in FIG 4, the current flow path in thethermopile 10 includes each of the thermoelectric layers 21 and each ofthe bases 16A, 16B and 16C of the heat exchangers 12A, 12B and 12C.Current passes from one of the bases 16 located at the upper level ofFIG. 4 to the juxtaposed base 16 located at the lower level of FIG. 4 bya current fiow path through electrically conductive heated heatexchangers 14, as will be described.

Viewing FIG. 3, it will be seen that current passes through the heatexchange structures 12 located at the upper level in FIG. 3 to thejuxtaposed heat exchange structures 12 located at the lower levelthrough layer 21 of thermoelectric material, heat exchange structure 14and a second thermoelectric layer 21. The heat exchange structures 14 ofthis illustrative embodiment of the invention are formed from twoseparate half-sized heat exchangers which are joined together atjuxtaposed surfaces 22 by suitable means as by brazing to produce anelectrically conductive joint therebetween. Each heat exchanger 14 isprovided with a pair of pedestal-type bases 24 at opposed ends thereofand with a plurality of electrically conductive fins extending betweenadpacent bases 24 and surfaces 22. The fins 26 located in planestransverse to the planes of the tins of the heat exchangers 12 aresecured at their ends to bases 24 and surfaces 22 in a manner to providegood electrical contact therebetween. The pedestal-type bases 24 of heatexchangers 14 are each formed with an outwardly extending projection 28with the projection having a cross-sectional area exactly equal to thecross-sectional area of the thermoelectric layers 21. Each heat exchangestructure 14 extends between opposed thermoelectric layers 21 andadjacent heat exchange structures 14 are maintained in insulatedrelationship with one another. Each of the heat exchangers 14 and 12A,12B and 12C are fixedly positioned by a pair of spaced grid structures30 and 32 having openings formed therein which receive the heatexchangers 12A, 12B and 12C. Grid structures 30 and 32 desirably areformed from an insulating material such as a polyester glass and aresecured together by a plurality of tie bolts 34 which pass throughsuitably aligned openings in the grid structures 30 and 32.

As seen in FIG. 1, a plurality of transversely extending tie rods 36extend across the outer surfaces (from left to right) of grid structures30 and 32 and which serve both to separate the adjacent rows of heatexchange structures 12 and to fixedly position adjacent ones of the heatexchange structure 12. Tie rods 36 desirably are formed from the samematerial as the grids 30 and 32 and are provided with circularprojections 38 adjacent the ends thereof through which the tie bolts 34extend. A generally moisture tight gasket 40 surrounds each of thethermoelectric layers 21 and is positioned in compression betweenjuxtaposed bases 16 and 24 of heat exchangers 12 and 14. Each of thegaskets 40 desirably has a generally U-shaped cross-section which isshaped complementarily with adjacent portions of the grids 30 and 32 toreceive the adjacent grid portions in the openrngs thereof. The gaskets40 serve to prevent moisture from corroding the joints betweenthermoelectric layers 21 and bases 16 and 24 and also to provide shockresist ance for the thermopile 10.

In an arrangement of the character described wherein a direct transferheat exchange device is provided having no electrical insulation in theflow path, the thickness of the pellet layers 21 (also known as thepellet length in the direction of the current flow) can be substantiallyreduced to lengths for example on the order of 0.1 inch. A pelletthickness of such a low magnitude positioned between a pair ofelectrically conducting base members such as the bases 16 and 24, whichhave a larger crosssectional area than the corresponding area of thepellet layers 21, increases substantially the possibility of arcingbetween the bases 16 and 24 in shunting relationship with the normalelectrical current path of the thermopile. In order to avoid suchpossibilities, at least one of the bases 16 and 24 is provided with thepedestal-type projection 28 of the same cross-sectional area as thethermoelectric layer 21 to effectively increase the distance betweenthese portions of the bases having no thermoelectric materialtherebetween. The provision of insulating material surrounding thepedestal projections 28 further serves to minimize the possibility ofarcing.

In the example of the invention illustrated herein, the heat exchangestructures 14 have a central partition 22 which provides additionalrigidity to the heat exchangers 14 particularly since the latter heatexchangers are subjected to compressive forces by the tie bolts 34. Itwill be appreciated, however, that the fins 26 can extend directlybetween juxtaposed bases 24 without the use of the partitions 22.

Each of the upper surfaces of the heat exchange housings 20B desirablyis provided with a terminal plate 42 fixedly secured to heat exchangestructures 12B by conventional means as brazing. Each terminal plate 42has an opening formed therein to which a lead wire 44 and terminalclamps 46 respectively are secured by conventional means such as machinescrew 48. Terminal clamps 46 are adapted to be connected to a source ofdirect current power which produces direct currents passing throughthermopile along the path illustrated schematically in FIG. 4. In theevent the thermopile 10 is utilized as an electrical generator of thethermoelectric type, air at different temperatures is selectively passedthrough heat exchangers l2 and 14 and thermoelectrically induced poweris provided at terminal plates 42 by the thermopile 10.

Referring now to the embodiment of the invention illustrated in FIG. 5,there is illustrated a modified form of the thermopile 10 of FIGS. 1through 4 in a dehumidification application. In this connection it willbe appreciated that exactly duplicated parts of the FIG. 5 embodimentwill be indicated by the same reference characters and such parts willnot be again described in detail. Equivalent or functionally similarparts will be indicated by primed reference characters.

In FIG. 5 a thermopile arrangement 10' is formed having a plurality ofheat exchangers 12A, 12B and 12C which are adapted to be cooled bythermoelectric layers 21. A plurality of heated heat exchange structures14' are formed between the two layers of cooled heat exchange structures12 and are similar to the heat exchange structures 14 of FIGS. 1, 2 and3 except for the positioning being of fins 26' thereof. In FIG. 5, thefins 26' extend parallel to the fins 18 of the heat exchangers 12. Eachof the heat exchangers I2 and 14' are fixedly positioned with thethermoelectric layers 21 secured thereto by a pair of grid structures 30and 32. The thermopile assembly 10' desirably is disposed in a generallycupshaped housing 50 and is fixedly positioned therein in insulatedrelationship with the walls of housing 50 by suitable means (not shown).A central conduit means 52 is secured at the upper end of thermopile 10and desirably is shaped to conform in cross-sectional area to the upperend cross-section of the flow space through heat exchangers 14.Accordingly, the housing structures 50 and 51 provide an inlet path forair flowing through the thermo pile 10 of generally annularcross-sectional configuration with air flowing into housing 50, asillustrated by How arrows 54. The inlet air passes through each of theheat exchange structures 12 and is cooled thereby to remove the moisturetherefrom. The air flow is then directed upwardly through each of theheat exchange structures 14' as indicated by the flow arrows 56 where itis reheated to substantially its inlet temperature and then exits fromthe dehumidifier through conduit 52. To assist the air circulationthrough the dehumidifier, an air circulating means shown schematicallyand referred to by reference character 58 is positioned within conduit52 to exhaust the air in the upward direction through the conduit 52.Moisture collecting on the fins of heat ex change structures 12 formsdroplets which fall to the bottom of housing 50 and are removed fromhousing 50 by a drain 59 formed in the lower end thereof. The drain 59is connected to a trap 61 which prevents the flow of air into housing 50through drain 59. By use of the annular suction flow path and centralexhaust path of the dehumidifier, such dehumidifiers can be constructedof minimized size and weight and the advantages of high efficicncy andlow weight thermo-electric material savings can be realized from theFIG. 5 arrangement. In the application of FIG. 5, direct current issupplied to the terminals 42 (not shown) of the thermopile l0 and thethermoelectric layers 20 are formed to provide thermoelectric cooling inthe annular space between housing 50 and grid structures 30 and 32 andthermoelectric heating in the central space between grid structures 30and 32.

Referring now to the embodiment of this invention illustrated in FIG. 6,it will be appreciated that the FIG. 6 arrangment provides a basicsub-module which may be grouped together into a complete module ofdifferent capacities, dependent upon the number of sub-modules, toprovide a predetermined amount of thermo-electric cooling or heating forany given application. In the arrangement of FIG. 6, three verticallyextending sub-modules 60 are illustrated, each submodule including sixlayers of thermoelectric materials 62 positioned between seven heatexchange structures in a vertical column and identified by the referencecharacters 64, 66 and 68. Each of the heat exchange structures 66 isadapted to be thermoelectrically cooled by the thermoelectric layer 62,while the heat exchangers 64 and 68, are adapted to be thermoelectrically heated. In furtherance of this purpose, a series currentflow path is formed through the adjacent heat exchange structures 64, 66or 68 and thermoelectric layers 62. The layers 62 are alternately formedfrom thermoelectrically positive and thermoelectrically negativematerial to produce the desired heating and cooling effects in thejunction members on opposite sides thereof. Each of the thermoelectricheat exchange structures 68 are provided with a plurality of spaced fins70 thereon which extend in FIG. 6 from the front of the thermopile tothe rear, while fins (not shown) of the heat exchangers 66 extendtransversely to the fins 70 (ie from the left of FIG. 6 to the right).The heat exchangers 64 desirably are half-sized to provide exactly halfthe heat transfer area as the heat exchangers 66 and 68 so that when twosub-modules 60 are joined together each adjacent pair of thermoelectriclayers 62 acts to heat or cool a substam tially equal efi'ective heattransfer surface area. In FIG. 6, the thermoelectric layers 62 aresecured to an adjacent base of one of the heat exchangers 64, 66 or 68.The jux taposed surface of the other adjacent heat exchange struc tureis provided with a projection or pedestal 72 thereon to which thethermoelectric layer 62 is secured, which ar rangement minimizes thepossibility of arcing between adjacent heat exchange structures, aspreviously described. In addition an annular gasket 74 (shown in sectionin FIG. 6) surrounds the outer periphery of each thermm zaisiz electriclayer 62 and pedestal 72. A terminal member designated generally by thereference character 76 is mounted on the outwardly facing surfaces ofthe end heat exchangers 64 and are positioned to be secured tocorresponding terminals of adjacent sub-modules by suitable means suchas electrically conducting transition members 78 and tie bolts 80.Terminals 76 are positioned so that corresponding rows of sub-modules 60may be electrically connected in series. In this manner an air-to-airthermoelectric heat exchange device, or alternatively, an air-to-airthermoelectric electrical generating device of any desired size andcapacity may be formed by assembling a predetermined number ofsub-modules 60. Suitable means may be provided for fixedly positioningthe sub-modules 60 relative to one another for example by the use ofspaced layers of insulating material and tie bolts (not shown) in anyconventional manner. In accordance with the invention, adjacentsub-modules 60 are mounted in electrically insulated relationship withone another either by providing a spaced relationship therebetween or byproviding layers of insulating material 82 or 84 between adjacent heatexchange structures. The insulating layers 82 disirably are providedwith a plurality of slots therein which conform with the spaces betweenthe adjacent fins of the heat exchanger 66 to provide a continuous fiowpassageway through the modules.

It will be appreciated by those skilled in the art that manymodifications may be made to the illustrative embodiments of theinvention illustrated herein without departing from the broad spirit andscope thereof. Accord ingly it is specifically intended that theembodiments of this invention described in detail herein be interpretedas illustrative of this invention, rather than as limitative thereof.

I claim as my invention:

[1. In a thermoelectric device, an electrically and thermally conductiveheat exchanger, said heat exchanger comprising a pair or spaced basemembers having a plurality of spaced fins extending laterally betweenand joined to said base members, a layer of thermoelectric materialmounted on each of said base members, one of said layers being formedfrom thermoelectrically positive material and the other of said layersbeing formed from thermoelectrically negative material, a plurality ofheat exchange fins secured to each of said thermoelectric layers,terminal means connected to said last mentioned fins to form a currentpath serially through said fins, said thermoelectric layers and throughsaid heat exchanger] [2. In a thermoelectric device, an electrically andthermally conductive heat exchanger, said heat exchanger comprising apair of spaced base members having a plurality of spaced generallyplanar fins extending laterally between and joined to said base members,a layer of thermoelectric material mounted on each of said base members,one of said layers being formed fromdhermoelectrically positive materialand the other of said layers being formed thermoelectrically negativematerial, a plurality of heat exchange fins secured to each of saidthermoelectric layers, said last mentioned fins extending in a planepositioned laterally with respect to the plane of said heat exchangerfins, terminal means connected to said heat exchange fins for passingcurrent serially through said fins, said thermoelectric layers andthrough said heat exchanger] [3. In a thermoelectrc device, a pair ofspaced heat exchangers formed from electrically and thermally conductivematerial, each of said heat exchangers including a base member and aplurality of spaced heat exchange fins extending laterally from saidbase member, a layer of thermoelectric material secured to a surface oneach of said base members, a heat exchange means including a pluralityof electrically conducting fins thereon mounted in bridging relationshipbetween said layers of thermoelectric material, whereby a series currentflow path is 8 surfaces, and a layei of iheriiiuelecti'ic riia'ieiiul otthe formed through said heat exchangers. said theimoelectric layers andsaid heat exchange means [4. In a thermoelectric device, a pair ofelectrically and thermally conductive heat exchangers, said heatexchangers being positioned in spaced relationship and each having onesurface thereof mounted in opposed relationship, one of said lastmentioned surfaces having a projection extending outwardly therefromtoward the other of said surfaces, said projection having a smallercross-sectional area than the cross-sectional area of said samecross-sectional area as said projection secured to said projection andto said other surface in electrically conductive relationship therewith][5. In a thermoelectric device. a pair of electrically and thermallyconductive heat exchangers, said heat exchangers being positioned inspaced relationship and each having one surface thereof mounted inopposed relationship, one of said last mentioned surfaces having aprojection extending outwardly therefrom toward the other of saidsurfaces, said proiection having a smaller cross-sectional area than thecross-sectional area of said surfaces, and a layer of thermoelectricmaterial of the same cross-sectional area as said projection secured tosaid projection and to said other surface in electrically conductiverelationship therewith, an insulating means filling the remainder of thespacing between said opposed surfaces] 6. In a thermoelectricdehumidifier, a generally cupshaped vessel, a thermoelectric heatexchanger disposed in said vessel, said heat exchanger comprising atleast three heat transfer means mounted in tandem forming a central andtwo outer heat transfer means and having thermoelectric materialpositioned between and secured to adjacent ones of said heat transfermeans, said thermoelectric material being of a polarity to inducethermoelectric cooling in the outer ones of said heat transfer means andthermoelectric heating in the central one of said heat transfer means,conduit means extending through the open end of said cup-shaped vesseland connected to said central heat transfer means, said vessel and saidconduit means forming an annular intake flow path to transmit air intocommunication with said [cooled] ourier transfer means, and said inletair supply exiting from said vessel through said central heat transfermeans and said conduit.

[7. In a thermoelectric device, a first and a second heat exchanger,each of said heat exchangers comprising a pair of spaced base memberssaid a plurality of heat exchange fins extending laterally between andsecured to each of said base members, a pair of layers of thermoelectricmaterial secured to said heat exchangers and mounted on said basemembers thereof respectively, a first heat transfer means comprising abase member and a plurality of laterally extending fins secured to oneof said thermoelectric layers of said first heat exchanger, 2. secondheat transfer means comprising a base member and a plurality oflaterally extending heat transfer fins secured to one of saidthermoelectric layers of said second heat exchanger, 21 third heattransfer means comprising a base member secured in bridging relationshipto the others of said thermoelectric layers of said first and saidsecond heat exchangers, said third heat transfer means having aplurality of spaced fins extending laterally from said base member, andterminal means connected to said first and said second heat transfermeans] [8. In a thermoelectric heating and cooling device, a first and asecond heat exchanger, each of said heat exchangers comprising a pair ofspaced base members and a plurality of laterally extending heat exchangefins secured to each of said base members, a pair of layers ofthermoelectric material secured to each of said heat exchangers andmounted on said base members, respectively, a first heat transfer meanscomprising a base member and a plurality of laterally extending finssecured to one of said thermoelectric layers of said first heatexchanger, a second heat transfer means comprising a base member and aplurality of laterally extending heat transfer fins secured to one ofsaid thermoelectric layers of said second heat exchanger, a third heattransfer means comprising a base member secured in bridging relationshipto the others of said thermoelectric layers of said first and saidsecond heat exchangers, said third heat transfer means having aplurality of spaced fins extending laterally from said base member, andterminal means connected to said first and said second heat transfermeans, said thermoelectric material being chosen of a polarity so as toprovide one of the conditions of thermoelectric heating andthermoelectric cooling to both said first and said second exchangers andto induce the other of said conditions of thermoelectric heating andthermoelectric cooling to each of said first, second and third heattransfer means] 9. The thermoelectric dehumidifier of claim 6 whereinsaid central heat transfer means includes a pair of spaced electricallyconducting base members and a plurality of electrically conductinggenerally planar central fins extending between and secured to said basemembers, and a layer of thermoelectric material coupled elec' tricallyand in heat exchongle relationship with each of said base member.

10. The thermoelectric dehumidifier of claim 9 wherein said two outerheat transfer means each includes an electrically conducting outer basemember, each outer base member being electrically coupled and in heatexchange relationship with the respective adjacent layer ofthermoelectric material.

1]. The thermoelectric dehumidifier of claim 10 wherein each of saidouter base members includes a plurality of generally planar electricallyconducting outer fins secured thereto and extending outwardly therefromin a direction away from said central heat transfer means, the planes ofsaid outer fins being substantially parallel to the plane of saidcentral fins.

12. In a thermoelectric dehumidifier, a generally cupshaped vessel, athermoelectric heat exchanger disposed in said vessel, said heatexchanger comprising at least three heat transfer means mounted intandem forming a central and two outer heat transfer means and havingthermoelectric material positioned between and secured to adjacent onesof said heat transfer means, said thermoelectric material being of apolarity to induce one of the conditions of thermoelectric heating andthermoelectric cooling in the outer ones of said heat transfer means andthe other of the conditions of thermoelectric cooling and thermoelectricheating in the central one of said heat transfer means, conduit meansextending through the open end of said cup-shaped vessel and connectedto Said central heat transfer means, said vessel and said conduit meansforming an intake flow path to transmit air mto communication with theones of said heat transfer means being thermoelectrically cooled, andsaid inlet air supply exiting from said vessel through the ones of saidheat transfer means being thermoelectrically heated.

13. The thermoelectric dehumidifier of claim 12 wherein said centralheat transfer means includes a pair of spaced electrically conductingbase members and a plurality of electrically conducting generally planarcentral fins extending between and secured to said base members, and alayer of thermoelectric material coupled electrically and in heatexchange relationship with each of said base members.

14. The thermoelectric dehumidifier of claim 13 wherein said two outerheat transfer means each includes an electrically conducting outer basemember, each outer base member being electrically coupled and in heatex= change relationship with the respective adjacent layer ofthermoelectric material.

15. The thermoelectric dehumidifier of claim 14 where in each of saidouter base members includes a plurality of generally planar electricallyconducting outer fins secured thereto and extending outwardly therefromin a direction away from said central heat transfer means, the planes ofsaid outer fins being substantially parallel to the plane of saidcentral fbts.

References Cited The following references, cited by the Examiner, are ofrecord in the patented file of this patent or the original patent.

UNITED STATES PATENTS 2,949,014 8/1960 Belton 62-3 3,024,616 3/1962 Bury62-3 3,040,538 6/1962 Alsing 62-3 3,077,080 2/1963 Pietsch 62-33,126,710 3/1964 Boehmer 62-3 3,137,142 6/1964 Venema 62-3 2,944,4047/1960 Fritts a- 62-3 3,036,383 5/1962 Edwards 62-3 3,095,709 7/1963Demand 62-3 WILLIAM I. WYE, Primary Examiner.

US. Cl. X11, 62-90

